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La evolución de las galaxias desde las irregulares primitivas hasta las elípticas actuales
1Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547, USA. mmori@isc.senshu-u.ac.jp
Nature
|March 31, 2006
Resumen
Este estudio simula la formación de galaxias desde las primeras etapas hasta los sistemas maduros. La simulación replica con éxito los tipos de galaxias observadas a través del tiempo cósmico, incluidos los emisores Lyman-alfa y las galaxias elípticas.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- Las simulaciones computacionales son simulaciones computacionales.
Sus antecedentes:
- Los modelos de formación de galaxias tradicionalmente luchan con el enfriamiento radiativo y la retroalimentación de supernovas.
- La fusión jerárquica de estructuras más pequeñas es el paradigma aceptado para el montaje de galaxias.
Objetivo del estudio:
- Para presentar una nueva simulación de seguimiento de la evolución de las galaxias desde la formación inicial hasta un estado final relajado.
- Para validar los resultados de la simulación frente a las observaciones de galaxias de alto desplazamiento al rojo y de galaxias actuales.
Principales métodos:
- Una simulación completa que incorpora procesos de enfriamiento radiativo y retroalimentación estelar.
- Seguimiento de la evolución del gas, las estrellas y las propiedades estructurales en escalas de tiempo cósmicas.
Principales resultados:
- Las primeras etapas de simulación (< 3 x 10^8 años) muestran estructuras de burbujas que se asemejan a emisores Lyman-alfa de alto desplazamiento al rojo.
- Las etapas intermedias (~ 10^9 años) exhiben un dominio del continuo estelar, similar a las galaxias de ruptura de Lyman con metalicidad solar.
- Las etapas tardías (~ 1,3 x 10^10 años) producen galaxias que se asemejan a las galaxias elípticas locales.
Conclusiones:
- La simulación proporciona un modelo unificado para la formación de galaxias consistente con los datos de observación a través de diferentes épocas cósmicas.
- El modelado preciso de la dinámica de los gases y la retroalimentación es crucial para comprender la evolución de las galaxias.
- La simulación reproduce con éxito las poblaciones clave de galaxias observadas en varios desplazamientos al rojo.
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